Tc 9-524 fundamentals of machine tools

Vertical Band Saw Operation
Straight-line sawing is performed on the vertical band saw
machine by using one or a combination of several
mechanisms or attachments: the miter guide attachment, with
or without power feed, with or without the work-holding jaw
device-. and the work-holding jaw device with power feed and
angular blade guide attachment.
The miter guide attachment on some machines can be
connected to the power feed mechanism and on others
must be fed by hand. The workpiece is clamped or hand-
held against the miter guide attachment and the workpiece
and attachment are moved on a track parallel to the blade,
thereby assuring a straight-line cut.
The work-holding jaw device on some machines can be
connected to the power feed to produce straight-line cuts
(Figure 6-18).
The angular blade guide attachment is used for straight-
line sawing when the workpiece cannot be cut in the usual
manner because it is too large or too long to clear the
column of the bar, sawing machine frame.
A typical example of straight-line sawing is outlined below :
Select a band saw blade of the desired pitch for the nature
of material to be cut. The blade should be as wide as
possible for straight-line sawing.
Set the desired speed on the bandsawing machine.
Position the workpiece at the desired angle in one of the
machine attachments and connect the cable to the power
feed mechanism if power feed is to be used.
Start the bandsawing machine and feed the workpiece
lightly into the blade to start the cut. Once the cut is
started, the feed can be increased. If feeding is by hand,
the pressure applied to the workpiece by the operator can
be varied to find the best cutting conditions.
RADIUS SAWING
Radius sawing is performed on the bandsaw by either
guiding the workpiece by hand or by using the disk-cutting
attachment.
Blade Selection
Care must be taken to select a bandsaw blade of the proper
width for the radius or circle to be cut. If the blade is too wide
for the radius, the heel of the blade will press against the outer
edge of the kerf (Figure 6-19). When the heel contacts this
edge, any further twisting of the workpiece in an attempt to
cut a sharper radius will twist the bandsaw blade and may
result in the blade breaking.